Blackburn have been left “bitterly disappointed” after losing their appeal against the EFL's refusal to ratify Lewis O'Brien's loan move from Nottingham Forest.
Rovers said their failure to complete all the required paperwork by 11pm on transfer deadline day was due to circumstances beyond their control.
But an independent arbitration panel ruled the EFL had made the correct decision and Rovers have been given no further grounds to appeal.
Rovers said in a statement: “The club challenged that decision on the basis of a legal interpretation of the regulations around meeting the relevant deadline.
“Unfortunately, the independently appointed arbitrator has now rejected Rovers' challenge and determined that the EFL correctly interpreted and applied its Regulations and associated Guidance.
“The club is bitterly disappointed by the outcome, but now accepts the decision. As there is no further right of appeal, Lewis O'Brien's registration will remain with Nottingham Forest.”
O'Brien responded to the news on Twitter, saying: “Absolutely gutted about the decision. Will come back stronger.”
Rovers' inability to register O'Brien was a source of frustration for Forest boss Steve Cooper, who left the player out of his 25-man Premier League squad in anticipation of his move.
Cooper said early last month: “It won't take a genius to work out what has happened. I hope some questions are getting asked over there in Lancashire.”
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